ANALISIS POSTUR KERJA KARYAWAN DALAM PENGANGKATAN TABUNG GAS ELPIJI DARI CONVEYOR

This firm still relies on physical labor to complete its tasks. Based on prior findings, it is anticipated that there may be instances where workers' work posture will be incorrect when doing duties in a bent position. Musculoskeletal Disorders (MSDs) can be caused by poor work posture. The goal of this study is to figure out how workers stand at work. REBA is the method that was employed. Pain was found in the waist, right wrist, left wrist, left calf, right calf, and back, according to the Nordic Body Map (NBM) questionnaire. Calculations were made using the REBA technique based on these data, and a score of 8 was obtained, putting it in the category of high danger and requiring rapid repair

Generalised connections over a vector bundle map

A generalised notion of connection on a fibre bundle E over a manifold M is presented. These connections are characterised by a smooth distribution on E which projects onto a (not necessarily integrable) distribution on M and which, in addition, is `parametrised' in some specific way by a vector bundle map from a prescribed vector bundle over M into TM. Some basic properties of these generalised connections are investigated. Special attention is paid to the class of linear connections over a vector bundle map. It is pointed out that not only the more familiar types of connections encountered in the literature, but also the recently studied Lie algebroid connections, can be recovered as special cases within this more general framework.Comment: 31 page

Representability of Hom implies flatness

Let $X$ be a projective scheme over a noetherian base scheme $S$, and let $F$ be a coherent sheaf on $X$. For any coherent sheaf $E$ on $X$, consider the set-valued contravariant functor $Hom_{E,F}$ on $S$-schemes, defined by $Hom_{E,F}(T) = Hom(E_T,F_T)$ where $E_T$ and $F_T$ are the pull-backs of $E$ and $F$ to $X_T = X\times_S T$. A basic result of Grothendieck ([EGA] III 7.7.8, 7.7.9) says that if $F$ is flat over $S$ then $Hom_{E,F}$ is representable for all $E$. We prove the converse of the above, in fact, we show that if $L$ is a relatively ample line bundle on $X$ over $S$ such that the functor $Hom_{L^{-n},F}$ is representable for infinitely many positive integers $n$, then $F$ is flat over $S$. As a corollary, taking $X=S$, it follows that if $F$ is a coherent sheaf on $S$ then the functor $T\mapsto H^0(T, F_T)$ on the category of $S$-schemes is representable if and only if $F$ is locally free on $S$. This answers a question posed by Angelo Vistoli. The techniques we use involve the proof of flattening stratification, together with the methods used in proving the author's earlier result (see arXiv.org/abs/math.AG/0204047) that the automorphism group functor of a coherent sheaf on $S$ is representable if and only if the sheaf is locally free.Comment: 9 pages, LaTe

Extending the double ramification cycle by resolving the Abel-Jacobi map

Over the moduli space of smooth curves, the double ramification cycle can be defined by pulling back the unit section of the universal jacobian along the Abel-Jacobi map. This breaks down over the boundary since the Abel-Jacobi map fails to extend. We construct a `universal' resolution of the Abel-Jacobi map, and thereby extend the double ramification cycle to the whole of the moduli of stable curves. In the non-twisted case, we show that our extension coincides with the cycle constructed by Li, Graber, Vakil via a virtual fundamental class on a space of rubber maps.Comment: 35 pages, 1 figure. v2:Exposition heavily revised (and hopefully improved). Main results unchanged. There was a gap in the proof of lemma 3.14; it is replaced by the construction in lemma 6.1. v3: Extended to include the `k-twisted' case, where one allows powers of the relative dualising sheaf. v4. Final version, to appear in J. Inst. Math. Jussieu. Comments still very welcom

The Chow ring of the stack of cyclic covers of the projective line

In this paper we compute the integral Chow ring of the stack of smooth uniform cyclic covers of the projective line and we give explicit generators.Comment: 20 pages; final version, to appear in Ann. Inst. Fourie